The invention relates to an adaptive corrector or equalizer for correcting or equalizing data signals which are respectively formed as a primary value and a plurality of prior and subsequent oscillations, and wherein the plurality of delay members which delay the data signals are provided. The signals are multiplied with alterable coefficients at the outputs of the delay members. At least one analog adder is provided which sums up the signals multiplied by the coefficients.
It is already known to use adaptive, i.e. automatically self-adjusting equalizers or correctors for the correction of the time characteristic of data signals. Such correctors are switched on in a data receiver following a demodulator for the data signals, but prior to a scanning stage and prior to a decoder. A particular advantage of the adaptive correctors is that they automatically adjust to the respective transmission channel properties at the beginning of a data transmission and that they can also control or regulate alterations of these properties during a transmission. Most of the adaptive correctors presently known are constructed of so-called echo correctors or transversal filters for a synchronous data transmission via band restricted transmission paths. A transversal filter consists of a delay line with taps spaced in correspondence with a time span which is assigned to the delay between two subsequent transmitted steps. An adjusting member is connected to each tap of the delay line which can exhibit an alterable amplification. The sum of the partial voltages, evaluated by coefficients appears at the output of the transversal filter. In the adaptive correctors or equalizers, the coefficients are altered for a sufficient length of time until a receiver impulse has the best possible form.
Pulse and carrier signals are synchronized in the data receiver during a transmission with the aid of the data signals received. The carrier signals are required for the demodulation of the data signals, and the pulse signals are required for the scanning of the data signals.
Interferring couplings between the adjustment of the coefficients and the pulse or carrier control or regulation can occur with the utilization of an adaptive corrector together with the pulse and carrier phase control or regulation stages.